1. Field of the Invention
The present invention generally relates to ram type compactors for use in compacting soils and more particularly to a novel and unique alignment mechanism between the upper portion of the machine and the lower portion of the machine in which the upper portion of the machine has a square guide tube forming a portion thereof and the lower portion of the machine has a spring housing provided with a square hole in the upper end in which the hole is lined with a segmental bearing in engagement with the square guide tube.
2. Description of the Prior Art
In the present construction of ram type compactors, it is desirable to maintain alignment between the gear case or upper portion of the compactor and the spring housing or lower portion of the compactor in order for the operator to more effectively operate and control the compactor. Present methods for accomplishing this include the use of a bellows type boot interconnecting the guide tube forming a portion of the gear case and the spring housing with the boot maintaining alignment to the extent that the boot has torsional resistance. As the boot is used, it becomes more flexible and weakens thereby reducing its torsional resistance. This decrease in torsional resistance permits misalignment between the gear case or upper portion of the machine and the spring housing with the tamping shoe thereon or the lower portion of the machine thereby creating handling and maneuverability problems. Another method which has been used to maintain alignment of the upper and lower portions of the compactor is the use of guide pins on one portion of the machine received in holes, slots or grooves in the other portion of the machine. The use of guide pins requires that the guide tube forming a portion of the gear case or upper portion of the machine and the spring housing maintain substantially constant orientation throughout the entire length of the stroke.
The following U.S. patents disclose various structures in ram type compactors, tamping devices and the like in which, in some instances, structures are provided to maintain alignment of the upper portion of the compactor and the lower portion thereof.
U.S. Pat. No. 3,017,810, 01/23/62
U.S. Pat. No. 3,073,219, 01/15/63
U.S. Pat. No. 3,236,164, 02/22/66
U.S. Pat. No. 3,286,790, 11/22/66
U.S. Pat. No. 4,104,001, 08/01/78